1. Field of the Invention
The present invention relates to a data processing device, a registration method for registering identification information for identifying the data processing device and an address of the data processing device, and a program for causing a computer to implement the registration method.
2. Description of the Related Art
A data processing device can automatically set an IP address of the data processing device itself while using a dynamic host configuration protocol (DHCP). This system is described, for example, in Japanese Patent Laid-Open No. 2000-244533 and Japanese Patent Laid-Open No. 2004-048462.
In a domain name system (DNS), an IP address and a host name of the data processing device are managed in association with each other. On the basis of this association, a corresponding IP address can be obtained from the host name, and a corresponding host name can be obtained from the IP address. This system is described, for example, in Japanese Patent Laid-Open No. 11-296467.
When the data processing device uses the DHCP, the IP address of the data processing device may be changed dynamically, and therefore the association between the IP address and the host name of the data processing device may also be changed. In that case, the association between the IP address and the host name cannot be managed properly in the DNS.
In view of the above, there is proposed a technology called dynamic DNS for dynamically updating a DNS record indicating the association between the host name and the IP address. In the dynamic DNS, a data processing device notifies a DNS server for managing the DNS record of the host name and the IP address and instructs the DNS server to register the DNS record. Then, the DNS server updates the DNS record in response to the instruction.
It should be noted that the registration of the DNS record cannot be instructed directly to the DNS server in some cases depending on the type of the data processing device. For example, there are cases where the DNS server accepts the registration of the DNS record only from specific devices for improving the security and a case where the DNS server accepts the registration of the DNS record only from devices located within the same domain.
In such cases, the data processing device cannot instruct the registration of the DNS record directly to the DNS server. Therefore, the data processing device sometimes uses an option of DHCP (for example, Option 81) to request a DHCP server to perform the registration of the DNS record with respect to the DNS server.
However, depending on the method of mounting the DHCP server or depending on the type of DHCP server, the DHCP server does not support the specific option (for example, Option 81) in some cases. Alternatively, even when the DHCP server supports the option (for example, Option 81), the data processing device may not be notified properly of the result regarding the registration of the DNS record. In that case, even when the data processing device requests the DHCP server to perform the registration of the DNS record, it is uncertain that the IP address and the host name of the data processing device are registered as the DNS record.
Thus, it is preferable that even when the address of the data processing device is dynamically assigned to the data processing device from the server, the association between identification information for identifying the data processing device and the address of the data processing device should be registered more reliably.